Sediment—or “the dregs,” as some kids call it—is a byproduct of winemaking. Most of it is made up of bits of grapes and seeds, dead yeast cells, crystal-like tartrates, or molecules called polymers. Sometimes winemakers filter or “fine” a wine to remove these solids, but even after being filtered and fined, it’s not unusual for wine to have sediment.

Sediment is also a result of aging, like wrinkles and grey hair are a result of giving wine advice. As wine ages, science happens, and phenolic molecules combine to form tannin polymers that fall out in the form of sediment. That’s also what causes an aging red wine’s color to fade—those phenolic molecules include pigmentation. I typically notice these changes around the 10-year mark for wine. To separate your wine from its sediment, you can check Decanting 101.

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